The invention relates to a recursive first order digital video signal filter comprising a combining circuit having a first input coupled to an input for a digital video signal of the filter, an output coupled via a signal path including a delay circuit to a second input of the combining circuit and a variable transfer circuit for controlling the ratio between the transferred portions of the signals applied to the first and second inputs, which transferred portions are contained in a signal at the output, the signal path comprising the delay circuit including a truncation circuit for reducing the number of bits conveyed through the signal path by cancelling a least significant portion of these bits.
BBC Report RD 1975/3 discloses a video signal filter of the above-defined type. Such a filter is often used as a noise suppression circuit. Because of the reduction by the truncation circuit of the number of bits fed back from the output to the second input of the combining circuit, the phenomenon occurs, at positive signal transients or negative pulses at the first input of the combining circuit that a residual value of the signal at the first input continues to circulate in the filter, which may result in annoying phenomena.